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Ali Hussein Kadhim was not supposed to live to tell his story or that of the hundreds of other Iraqi soldiers and Shiites who were massacred in June by ISIS militants in Tikrit.

But on the execution line that day the bullet destined for him whizzed past his head and he fell forward feigning to be fatally wounded. Kadhim lived to tell his story to the New York Times, which produced a gripping video offering a rare survivor's retelling of one of countless massacres carried out by the brutal Islamic State in Iraq and Syria.

"It took 23 days from the day of the massacre until he was reunited with his family," Adam Ellick, a senior video journalist for the New York Times, told CNN Thursday. "I think the best way I would describe it is a combination Schindler's List-style escape and an Underground Railroad of local Samaritans sort of putting humanity before everything else."

Brutality has become a propaganda tool for the militants. It has included processions of soldiers making their way across the desert in their underwear before facing a hail of bullets, the beheading of American journalists and even crucifixions. The militants often capture the killings on videos distributed throughout the world like bloody calling cards of their cruel campaign.